OBJECTIVES: To investigate the Chronic Obstructive Pulmonary Disease (COPD) prevalence, mortality, disease progression and associated co-morbidities in United States (US).

METHODS: Comprehensive literature search was conducted in PubMed and Cochrane Library by combination of MeSH terms & keywords from May 2017 to May 2018. Google & Google Scholar was also searched for any additional publications. The quality of included studies was assessed by Newcastle-Ottawa Scale (NOS). Studies investigating the COPD prevalence, mortality, disease progression and associated co-morbidities in the US were included.

RESULTS: The age-adjusted diagnosed COPD prevalence rate among adults aged ≥18 years was 5.9% (95% CI 5.8−6.0) in 2015. It was highly prevalent in West Virginia (12.0%) & lower in Utah (3.8%). Age-standardised COPD mortality rate was 45.1 & 40.3 per 100,000 populations in 2014 and 2015, respectively and it was increased between 1980 and 2014 (34.5 to 45.1 deaths per 100,000 populations). Older age (β=0.03058), lower BMI (β=-0.0569), airway disease axis (β=0.64179), and CT intensity variability/noise (β=0.30924) were significantly (p<0.0001) associated with higher mortality. Almost half (49%; N=1105) of the COPD patients had at least one acute exacerbation. 7% & 2% of patients had at least one & ≥2 acute exacerbation each year, respectively. Mean number of overall & severe exacerbations were 1.5 & 0.48, respectively. COPD patients with previous exacerbations (5.22), ≥2 exacerbations in the year preceding enrollment (3.03), lower baseline FEV1 (0.93), younger age (0.69) and higher CAT score (1.11) times significantly (p<0.001) higher odds to have at least one exacerbation. Very commonly reported co-morbidities in COPD patients were hypertension (46-63.2%), diabetes (28.3-31%), affective disorders (27%), congestive heart failure (26.9%), and fluid and electrolyte disorder (23.4%). Increasing trends were observed in most of the co-morbidities from 2006 to 2011.

CONCLUSIONS: COPD is highly prevalent and associated with significant morbidity, and mortality in the US.